Wire connector clamp



Feb. 6, 1962 w. L. BUTLER 3,020,514

WIRE CONNECTOR CLAMP Filed Dec. 16. 1960 Fig.2.

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Inventor: William Lawrence Butler;

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United States Patent" Otifice 3,020,514 WIRE CONNECTOR CLAMP WilliamLawrence Butler, Hendersonville, N.C., assignor to General ElectricCompany, a corporation of New York Filed Dec. 16, 1960, Ser. No. 76,2108 Claims. (Cl. 339-95) This invention relates generally to wireconnectors and more particularly to a clamp for securing a wire to sucha connector.

It is frequently necessary to connect the end of an electrical conductoror wire to some apparatus. Often for these purposes an intermediatemember or wire connector is used to make the connection to theapparatus.

An electrically good solderless connection can be made if the oxidationon the wire surface is broken by clamping action or some other method,and this will occur if the edges of a clamp are caused to bite into thewire.

A clamp, to be practically acceptable, should be simple both instructure and in operation and it should be relatively inexpensive.

Therefore, it is an object of this invention to provide a wire connectorclamp'which is simple to manufacture.

It is also an object of this invention to provide a wire connector clampwhich is easily clamped to a Wire.

It is a further object .of this invention to provide an inexpensiveexpendable clamp for a wire connector.

Briefly stated, in carrying out the invention in one 'form' which may bepreferred, a wire connector clamp is ar ranged to comprise three platemembers joined along one edge so as to form acute dihedral anglesbetween adjacent plate surfaces. The central plate extends from thejunction of these plates a greater distance than the other two platesand is provided with a wire receiving aperture having its center locatedat 'a point displaced from the junction approximately the same distanceas the ends of the other plates are from the junction. In use, a wire,

is placed through the aperture in the central plate and thereafter theouter plates are biased to overlie the central plate thereby causing theouter plates to bite into and clamp the wire to hold it fast. The clampmay be secured to a wire connector or other desired apparatus, either bythe same device used to bias the plates together, or by some othermeans.

. The invention will be'better understood from the following descriptiontaken in connection with the accompanying drawings, inwhich the FIG. 1is an exploded perspective view of a wire connector clamp according tothe invention; FIG. 2 is a view in section illustrating the clamp ofFIG. 1 to a terminal plate; and FIG. 3 is a modification.

Referring now to the drawing, and particularly to FIG. 1, a wire 1 isshown which may be electrically connected to the metal bar 2 thatrepresents some portion of a wire connector or apparatus terminalmember. This connection can be accomplished by using the clamp 3, of theinvention, which may be bent from an elongated plate into thesubstantially psi-shaped cross-section shown. As shown, the inner twolegs 4 and 5 are folded until their adjacent surfaces overlie in contactWith' each other to form essentially a single plate member generallyshown at 20. The outer two legs 6 and 7 are folded so as to make acutedihedral angles with the opposing plane surfaces of the inner leg 20.The apexes 8 and 9 respectively of the two acute dihedral angles may bepositioned so as to provide a substantially common junction of the legs4, 5, 6 and 7 along one edge thereof. This common positioning of theapexes is convenient for purposes of description and may facilitate themanufacturing of the clamps, but it is not essential to the int 2vention since, for example, either apex 8 or 9 may be located at adiiferent relative position.

As the drawing shows, the outer legs 6 and 7 extend a shorter distancefromthe apexes 8 and 9 respectively than does the central leg 20. Awirereceiving aperture 10 passes through the inner leg 20 with itscenter at such a point that the ends 11 and 12 respectively of. the

As is further shown by the drawings, an aperture 13 in the leg 6, asimilar aperture 14 in the leg 7, and an aperture 15 passing through thecenter leg 20 are provided. The last mentioned apertures 13, 14 and 15are made large enough to receive a fastener 16 or the like in a mannerto be later described, and may be designated as.

fastener receiving apertures.

As the drawing shows, a headed fastener such as the threaded screw '16is provided having a threaded shank portion 17. The screw 16 serves tosecure the clamp 3 to the metal bar 2 which therefore may be providedwith an' internally threaded aperture 18. In securing the clamp 3 to themetal bar 2, the screw 16 also brings. the outer legs 6 and 7 of theclamp into juxtaposition with the innerleg 20. In order to permit theshank 17 of the screw 16 to pass through the apertures 13, 14 and 15when the clamp 3 is in the position shown, and still not bind the shankwhen the legs are in juxtaposition, the outer apertures 13 and 14 may bemade large enough to be somewhat elliptical as shown. A Wire receivingaperture 19 may be provided on the metal bar 2 in a location determinedby that of the apertures already described to be in alignment withaperture 10 when the clamp 3 is secured to the connector bar 2 tothereby permit the wire 1 to be passed through both apertures 10 and 19when clamped.

In use, the end of the wire 1, stripped of any insulation," is insertedinto the wire receiving aperture 10 of the clamp '3 and the aperture 19of the connector bar 2. A screw 16 is then inserted into the apertures13, 14 andrlS, and is then screwed into the internally threaded aperture18 on the metal bar 2. It is evident that as the screw forces the outerlegs 6 and 7 of the clamp towards the inner leg 20 that the ends 11 and12 of the outer legs 6 and 7 will begin to bite into the wire 1. Whenthe parts are correctly sized, it will be found that the wire 1 isfirmly secured in the clamp 3 and to the metal bar 2. Because the ends11 and 12 of the legs 6 and 7 actually imbed themselves in the metal ofthe wire 1, a good electrical connection is made and, in fact, it willbe found that subsequent removal of the screw 16 will not release thewire 1 from the clamp 3. The end of the wire 1 when once secured toclamp 3 can be moved from one metal bar 2 to another at will without thenecessity of utilizing a new clamp. On the other hand, the simplestructure of the clamp 3 facilitates mass production of this part with aresulting small unit cost. If, for some reason, it becomes desirable toremove the clamp, it can be clipped olf with the end of the wire 1without substantial financial loss.

Conventional connectors which complete the connection by tightening ascrew require the wire to be inserted under the screw in a direction atright angles to the axis of the screw and the screw driver unless thewire is preformed or is provided with a previously attached terminal. Incompleting a connection with the connector of this invention, the wireis inserted in the wire receiving aperture 10 by a longitudinal axialmovement parallel Patented F elm. 6,. 1 962 x to the axis of the screwdriver that is being used to tighten the screw. The importance of thisWill be recognized when considered in relation to the trend towardminiaturization with the resulting crowding of wires on the backs ofpanels on which electrical components are mounted.

By the foregoing, the invention has been particularly described inconnection with a connector clamp 3 formed of a single strip of sheetmetal. It should be obvious that the plate members 6, 7 and 20 may beformed of individual plate elements joined together along a common edgeto form the equivalents of the apexes 8 and 9. It should also be notedthat although an aperture 19 has been described in the metal connectorbar 2 the provision of such aperture is not essential since the clampmay be connected to the bar member 2 at such an angle that the end ofthe wire 1 does not have to pass through any portion of the connectorbar 2. However, the use of the aperture 19 in some instances may bepreferred since it minimizes the tendency of the end of the wire 1 to bedeformed away from the end 12 of the clamping plate 7 as the clamp isapplied.

In the modified form illustrated in FIG. 3 the two outer legs 6 and 7are curved with their concave surfaces facing the central leg 20. Thisresults in reduction of the screw travel and in reduction of the lengthof the stripped portion of the wire.

While a particular embodiment of a wire connector clamp employing thisinvention has been shown andv described, it will be obvious that changesand modifications can be made without departing from the spirit of theinvention and the scope of the appended claims.

What is claimed as new and desired to be secured by Letters Patent ofthe United States is:

1. A wire connector clamp comprising a first plate member, a secondplate member secured at one edge of said first plate member and forminga first acute dihedral angle with one surface of said first platemember, a third plate member secured to said one edge of said firstplate member and forming a second acute dihedral angle with the oppositesurface of said first plate member, said first plate member having awire receiving aperture at a point displaced from said one edge adistance such that said second and third plate members will partiallyoverlie said wire receiving aperture when said second and third platemembers are brought into juxtaposition with said first plate member, andmeans for bringing said second and third plate members intojuxtaposition with said first plate member with a wire in said wirereceiving aperture whereby said wire is clamped to said wire connectorclamp.

2. A wire connector clamp as defined in claim 1 wherein said first,second and third plate members each have a. fastener receiving aperturefor receiving said means.

3. A wire connector clamp as defined in claim 2 in combination with awire connector having an internally threaded aperture wherein said meansis a headed fastener having a threaded shank passing through saidfastener receiving apertures to engage said threaded aperture.

4. A wire connector clamp comprising an elongated member folded to agenerally psi-shaped cross-section, said member when folded having twoinner legs with wire receiving apertures passing through both of saidlegs, two outer legs with the ends of said legs extending partially oversaid aligned wire receiving apertures when all of said legs are broughtinto juxtaposition, and means for bringing said inner and outer legsinto juxtaposition with a wire in said wire receiving aperture wherebysaid wire is clamped to said wire connector clamp.

5. A wire connector clamp as defined in claim 4 wherein said inner andouter legs have fastener receiving apertures for receiving said means.

6. A wire connector clamp as defined in claim 5 in combination with awire connector having an internally threaded aperture wherein said meansis a headed fastener having a threaded shank passing through saidfastener receiving apertures to engage said threaded aperture.

7. A Wire connector clamp as defined in claim 6 wherein said two innerlegs form a single plate.

8. A wire connector clamp comprising a central leg, a pair of curvedouter legs joined to one edge of said central leg with their concavefaces toward said central leg and forming acute angles therewith, saidcentral leg having a wire receiving aperture at a point displaced fromsaid edge a distance such that said curved legs will partially overliesaid wire receiving aperture when said curved legs are brought into faceto face contact with said central leg and means for bringing saidcentral and outer legs into face to face contact with each other with awire in said wire receiving aperture to effect clamping of said wire tosaid clamp.

References Cited in the file of this patent UNITED STATES PATENTS1,152,892 Henry Sept. 7, 1915 2,685,720 Petri Aug. 10, 1954 2,713,386Holtz July 19, 1955 2,768,363 Haynes Oct. 23, 1956

